Japanese Patent Application No. 2010-157505A discloses a conventional electrical connector that transmits a differential signal. The connector has a plurality of contacts having contact end portions positioned in two rows along a mating face, and contact terminating portions extending in one row out of a circuit board mounting side of the connector. The contact terminating portions extend in one row, because if the contacts terminating portions on circuit board mounting side were in a two row configuration similar to the contact end portions on the mating end, inspection or repair of soldering of an inner row would be obstructed by an outer row. Therefore, particularly in surface mounted connectors, the contact terminating portions are conventionally arranged in one row.
However, since all of the contact terminating portions extend in one row, the width of the electrical connector will be longer than a connector having the contact terminating portions extending in a two row configuration from the circuit board mounting side. The width presents a limitation in designing electrical connectors that are smaller in size. There is a need for a connector having a two-row contact end portion configuration on a mating face of the connector, and a row of contact terminating portions extending from the circuit board mounting with a smaller width, while not obstructing the inspection or repair of soldering.